1. Field of the Invention
The present invention relates generally to improvements in a microwave oven, and more particularly, pertains to a new and improved method of fire detection in a microwave oven heating cavity.
2. Description of the Prior Art
Those concerned with the development of microwave ovens have long recognized the need for an accurate method of fire detection in a microwave oven heating cavity. The present invention fills this need.
Past devices have filed to accurately determine a fire condition in a microwave oven heating cavity. While microwave ovens cook with "cool" microwave energy, sometimes it occurs that a cook will let a particular food cook longer than required or fail to turn the microwave oven off, thereby causing the food to overheat and combust resulting in a fire condition in the microwave oven heating cavity.
Smoke sensors cannot be located in the duct connecting the microwave oven heating cavity to the outside environment, as such sensors would be unsatisfactory due to dynamic gas flow within the duct system and the time lag taking the smoke to travel from the microwave oven cavity through the duct system to the point at which the sensor senses the smoke. Also, it has been impossible to locate fire sensors directly in the microwave oven heating cavity to electromagnetic interference consideration.
This invention, method of fire detection in a microwave oven, overcomes these disadvantages by providing an accurate and responsive sensing system of the time dependent "in-situ" environmental conditions of the microwave oven heating cavity when a fire occurs.